February 2004 - Musk leads Tesla Motors' initial round of investment funding, and joins the company as chairman of the board.

October 2008 - In addition to serving as board chairman, becomes CEO and product architect of Tesla Motors.

December 8, 2010 - SpaceX becomes the first privately owned company to return a commercial spacecraft from a low-Earth orbit.

May 25, 2012 - SpaceX's unmanned Dragon spacecraft makes history as the first private capsule to connect to the International Space Station (ISS).

May 31, 2012 - After delivering more than 1,000 pounds of cargo, including food, clothing, computer equipment and supplies for science experiments to the ISS, the first successful commercial mission ends with the SpaceX Dragon capsule splashing down about 560 miles off Baja California. Musk declares the flight a "grand slam."

November 2013 - Named Fortune's Businessperson of the Year.

December 11, 2015 - Along with other big name technology sponsors, announces plans to invest in the non-profit artificial intelligence research center OpenAI.

April 8, 2016 - For the first time, SpaceX successfully lands its Falcon 9 rocket on a drone ship.

March 2017 - Ranked number 80 on Forbes' list of The World's Billionaires, with a net worth of $13.9 billion.

March 30, 2017 - SpaceX successfully launches a used rocket. This is the first time in the history of spaceflight that the same rocket has been used on two separate missions to orbit.

June 1, 2017 - Quits two of President Donald Trump's business advisory councils after the president announces he will pull the US out of the historic Paris climate agreement. Musk tweets, "Am departing presidential councils. Climate change is real. Leaving Paris is not good for America or the world."

June 7, 2017 - Tesla lands on the Fortune 500 list of the nation's largest companies for the first time, landing at number 383. The list ranks companies by revenue, and Tesla pulled in $7 billion in 2016.